/*
  Copyright (C) 1997-2011 Sam Lantinga <slouken@libsdl.org>

  This software is provided 'as-is', without any express or implied
  warranty.  In no event will the authors be held liable for any damages
  arising from the use of this software.

  Permission is granted to anyone to use this software for any purpose,
  including commercial applications, and to alter it and redistribute it
  freely.
*/

/* Bring up a window and play with it */

#include <stdlib.h>
#include <stdio.h>
#include <string.h>

#define BENCHMARK_SDL

#define NOTICE(X)	printf("%s", X);

#include "SDL.h"

/* Call this instead of exit(), so we can clean up SDL: atexit() is evil. */
static void
quit(int rc)
{
    SDL_Quit();
    exit(rc);
}

void
DrawPict(SDL_Surface * screen, char *bmpfile,
         int speedy, int flip, int nofade)
{
    SDL_Surface *picture;
    SDL_Rect dest, update;
    int i, centered;
    int ncolors;
    SDL_Color *colors, *cmap;

    /* Load the image into a surface */
    if (bmpfile == NULL) {
        bmpfile = "sample.bmp"; /* Sample image */
    }
    fprintf(stderr, "Loading picture: %s\n", bmpfile);
    picture = SDL_LoadBMP(bmpfile);
    if (picture == NULL) {
        fprintf(stderr, "Couldn't load %s: %s\n", bmpfile, SDL_GetError());
        return;
    }

    /* Set the display colors -- on a hicolor display this is a no-op */
    if (picture->format->palette) {
        ncolors = picture->format->palette->ncolors;
        colors = (SDL_Color *) malloc(ncolors * sizeof(SDL_Color));
        cmap = (SDL_Color *) malloc(ncolors * sizeof(SDL_Color));
        memcpy(colors, picture->format->palette->colors,
               ncolors * sizeof(SDL_Color));
    } else {
        int r, g, b;

        /* Allocate 256 color palette */
        ncolors = 256;
        colors = (SDL_Color *) malloc(ncolors * sizeof(SDL_Color));
        cmap = (SDL_Color *) malloc(ncolors * sizeof(SDL_Color));

        /* Set a 3,3,2 color cube */
        for (r = 0; r < 8; ++r) {
            for (g = 0; g < 8; ++g) {
                for (b = 0; b < 4; ++b) {
                    i = ((r << 5) | (g << 2) | b);
                    colors[i].r = r << 5;
                    colors[i].g = g << 5;
                    colors[i].b = b << 6;
                }
            }
        }
    }
    NOTICE("testwin: setting colors\n");
    if (!SDL_SetColors(screen, colors, 0, ncolors) &&
        (screen->format->palette != NULL)) {
        fprintf(stderr,
                "Warning: Couldn't set all of the colors, but SDL will map the image\n"
                "         (colormap fading will suffer - try the -warp option)\n");
    }

    /* Display the picture */
    if (speedy) {
        SDL_Surface *displayfmt;

        fprintf(stderr, "Converting picture\n");
        displayfmt = SDL_DisplayFormat(picture);
        if (displayfmt == NULL) {
            fprintf(stderr, "Couldn't convert image: %s\n", SDL_GetError());
            goto done;
        }
        SDL_FreeSurface(picture);
        picture = displayfmt;
    }
    printf("(image surface located in %s memory)\n",
           (picture->flags & SDL_HWSURFACE) ? "video" : "system");
    centered = (screen->w - picture->w) / 2;
    if (centered < 0) {
        centered = 0;
    }
    dest.y = (screen->h - picture->h) / 2;
    dest.w = picture->w;
    dest.h = picture->h;
    NOTICE("testwin: moving image\n");
    for (i = 0; i <= centered; ++i) {
        dest.x = i;
        update = dest;
        if (SDL_BlitSurface(picture, NULL, screen, &update) < 0) {
            fprintf(stderr, "Blit failed: %s\n", SDL_GetError());
            break;
        }
        if (flip) {
            SDL_Flip(screen);
        } else {
            SDL_UpdateRects(screen, 1, &update);
        }
    }

#ifdef SCREENSHOT
    if (SDL_SaveBMP(screen, "screen.bmp") < 0)
        printf("Couldn't save screen: %s\n", SDL_GetError());
#endif

#ifndef BENCHMARK_SDL
    /* Let it sit there for a while */
    SDL_Delay(5 * 1000);
#endif
    /* Fade the colormap */
    if (!nofade) {
        int maxstep;
        SDL_Color final;
        SDL_Color palcolors[256];
        struct
        {
            Sint16 r, g, b;
        } cdist[256];

        NOTICE("testwin: fading out...\n");
        memcpy(cmap, colors, ncolors * sizeof(SDL_Color));
        maxstep = 32 - 1;
        final.r = 0xFF;
        final.g = 0x00;
        final.b = 0x00;
        memcpy(palcolors, colors, ncolors * sizeof(SDL_Color));
        for (i = 0; i < ncolors; ++i) {
            cdist[i].r = final.r - palcolors[i].r;
            cdist[i].g = final.g - palcolors[i].g;
            cdist[i].b = final.b - palcolors[i].b;
        }
        for (i = 0; i <= maxstep / 2; ++i) {    /* halfway fade */
            int c;
            for (c = 0; c < ncolors; ++c) {
                colors[c].r = palcolors[c].r + ((cdist[c].r * i)) / maxstep;
                colors[c].g = palcolors[c].g + ((cdist[c].g * i)) / maxstep;
                colors[c].b = palcolors[c].b + ((cdist[c].b * i)) / maxstep;
            }
            SDL_SetColors(screen, colors, 0, ncolors);
            SDL_Delay(1);
        }
        final.r = 0x00;
        final.g = 0x00;
        final.b = 0x00;
        memcpy(palcolors, colors, ncolors * sizeof(SDL_Color));
        for (i = 0; i < ncolors; ++i) {
            cdist[i].r = final.r - palcolors[i].r;
            cdist[i].g = final.g - palcolors[i].g;
            cdist[i].b = final.b - palcolors[i].b;
        }
        maxstep /= 2;
        for (i = 0; i <= maxstep; ++i) {        /* finish fade out */
            int c;
            for (c = 0; c < ncolors; ++c) {
                colors[c].r = palcolors[c].r + ((cdist[c].r * i)) / maxstep;
                colors[c].g = palcolors[c].g + ((cdist[c].g * i)) / maxstep;
                colors[c].b = palcolors[c].b + ((cdist[c].b * i)) / maxstep;
            }
            SDL_SetColors(screen, colors, 0, ncolors);
            SDL_Delay(1);
        }
        for (i = 0; i < ncolors; ++i) {
            colors[i].r = final.r;
            colors[i].g = final.g;
            colors[i].b = final.b;
        }
        SDL_SetColors(screen, colors, 0, ncolors);
        NOTICE("testwin: fading in...\n");
        memcpy(palcolors, colors, ncolors * sizeof(SDL_Color));
        for (i = 0; i < ncolors; ++i) {
            cdist[i].r = cmap[i].r - palcolors[i].r;
            cdist[i].g = cmap[i].g - palcolors[i].g;
            cdist[i].b = cmap[i].b - palcolors[i].b;
        }
        for (i = 0; i <= maxstep; ++i) {        /* 32 step fade in */
            int c;
            for (c = 0; c < ncolors; ++c) {
                colors[c].r = palcolors[c].r + ((cdist[c].r * i)) / maxstep;
                colors[c].g = palcolors[c].g + ((cdist[c].g * i)) / maxstep;
                colors[c].b = palcolors[c].b + ((cdist[c].b * i)) / maxstep;
            }
            SDL_SetColors(screen, colors, 0, ncolors);
            SDL_Delay(1);
        }
        NOTICE("testwin: fading over\n");
    }

  done:
    /* Free the picture and return */
    SDL_FreeSurface(picture);
    free(colors);
    free(cmap);
    return;
}

int
main(int argc, char *argv[])
{
    SDL_Surface *screen;
    /* Options */
    int speedy, flip, nofade;
    int delay;
    int w, h;
    int desired_bpp;
    Uint32 video_flags;
#ifdef BENCHMARK_SDL
    Uint32 then, now;
#endif
    /* Set default options and check command-line */
    speedy = 0;
    flip = 0;
    nofade = 0;
    delay = 1;

#ifdef _WIN32_WCE
    w = 240;
    h = 320;
    desired_bpp = 8;
    video_flags = SDL_FULLSCREEN;
#else
    w = 640;
    h = 480;
    desired_bpp = 0;
    video_flags = 0;
#endif
    if (SDL_Init(SDL_INIT_VIDEO) < 0) {
        fprintf(stderr, "Couldn't initialize SDL: %s\n", SDL_GetError());
        return (1);
    }

    while (argc > 1) {
        if (strcmp(argv[1], "-speedy") == 0) {
            speedy = 1;
            argv += 1;
            argc -= 1;
        } else if (strcmp(argv[1], "-nofade") == 0) {
            nofade = 1;
            argv += 1;
            argc -= 1;
        } else if (strcmp(argv[1], "-delay") == 0) {
            if (argv[2]) {
                delay = atoi(argv[2]);
                argv += 2;
                argc -= 2;
            } else {
                fprintf(stderr, "The -delay option requires an argument\n");
                quit(1);
            }
        } else if (strcmp(argv[1], "-width") == 0) {
            if (argv[2] && ((w = atoi(argv[2])) > 0)) {
                argv += 2;
                argc -= 2;
            } else {
                fprintf(stderr, "The -width option requires an argument\n");
                quit(1);
            }
        } else if (strcmp(argv[1], "-height") == 0) {
            if (argv[2] && ((h = atoi(argv[2])) > 0)) {
                argv += 2;
                argc -= 2;
            } else {
                fprintf(stderr, "The -height option requires an argument\n");
                quit(1);
            }
        } else if (strcmp(argv[1], "-bpp") == 0) {
            if (argv[2]) {
                desired_bpp = atoi(argv[2]);
                argv += 2;
                argc -= 2;
            } else {
                fprintf(stderr, "The -bpp option requires an argument\n");
                quit(1);
            }
        } else if (strcmp(argv[1], "-warp") == 0) {
            video_flags |= SDL_HWPALETTE;
            argv += 1;
            argc -= 1;
        } else if (strcmp(argv[1], "-hw") == 0) {
            video_flags |= SDL_HWSURFACE;
            argv += 1;
            argc -= 1;
        } else if (strcmp(argv[1], "-flip") == 0) {
            video_flags |= SDL_DOUBLEBUF;
            argv += 1;
            argc -= 1;
        } else if (strcmp(argv[1], "-fullscreen") == 0) {
            video_flags |= SDL_FULLSCREEN;
            argv += 1;
            argc -= 1;
        } else
            break;
    }

    /* Initialize the display */
    screen = SDL_SetVideoMode(w, h, desired_bpp, video_flags);
    if (screen == NULL) {
        fprintf(stderr, "Couldn't set %dx%dx%d video mode: %s\n",
                w, h, desired_bpp, SDL_GetError());
        quit(1);
    }
    printf("Set%s %dx%dx%d mode\n",
           screen->flags & SDL_FULLSCREEN ? " fullscreen" : "",
           screen->w, screen->h, screen->format->BitsPerPixel);
    printf("(video surface located in %s memory)\n",
           (screen->flags & SDL_HWSURFACE) ? "video" : "system");
    if (screen->flags & SDL_DOUBLEBUF) {
        printf("Double-buffering enabled\n");
        flip = 1;
    }

    /* Set the window manager title bar */
    SDL_WM_SetCaption("SDL test window", "testwin");

    /* Do all the drawing work */
#ifdef BENCHMARK_SDL
    then = SDL_GetTicks();
    DrawPict(screen, argv[1], speedy, flip, nofade);
    now = SDL_GetTicks();
    printf("Time: %d milliseconds\n", now - then);
#else
    DrawPict(screen, argv[1], speedy, flip, nofade);
#endif
    SDL_Delay(delay * 1000);
    SDL_Quit();
    return (0);
}
